Effects of leaf properties on the counts of microbes on the leaf surfaces of wheat, rye and triticale

Currently, our understanding of the effects of glaucousness on the population sizes of microbial communities on leaf surfaces is limited. The objective of this study was to investigate the influence of glaucousness and chemical composition on the colony-forming unit (CFU) counts of microbes on leaf surfaces. Various leaf morphological and physicochemical features, microbial CFU counts and glaucousness on the leaf surfaces of wheat (Triticum aestivum var. Shimai No.1), rye (Secale cereale var. Gannong No.1) and triticale (Triticale wittmack var. Gannong No.2) were assessed. The results showed that larger CFU counts of lactic acid bacteria (LAB) and yeasts were found on the non-glaucous leaf surfaces in wheat than on the glaucous leaf surfaces in rye and triticale. The CFU counts of LAB and yeasts were negatively correlated with the amount of soluble wax (P < 0.05), and positively correlated with the contents of starch and fructose in leaf tissue (P < 0.05), soluble and reduced sugars, soluble protein and free amino acids on leaf surfaces (P < 0.05). The CFU counts of microbes on leaf surfaces were mainly influenced by the level of available carbon sources and glaucousness of leaf surfaces. The wheat leave surfaces without glaucousness were more colonized by lactic acid bacteria and yeasts than the rye and trticale surfaces with glaucousness.